The field of the disclosure relates generally to electromagnetic projectile launching, and more particularly, to apparatus, methods and systems for electromagnetic projectile launching.
Known electromagnetic launching systems generally utilize an electromagnetic force, particularly the Lorentz force, to accelerate and launch a projectile. Two common types of electromagnetic launch systems are railguns and coilguns.
In a typical railgun system, a launch package slides between a pair of generally parallel rails. The launch package includes a payload coupled to an armature that functions as a sliding switch or an electrical short between the rails. In at least some known systems, launch packages include a sabot. By passing a large electrical current through one rail, through the armature, and back along the other rail, a large magnetic field is generated behind the launch package. The rapidly changing magnetic field within the boundaries of the two rails accelerates the launch package to a high velocity accordingly.
Electromagnetic coilgun systems include one or more electrical coils. In some systems, the coils surround a barrel. A launch package, including a payload and an armature, is positioned within the barrel. In other systems, the coils do not surround a barrel and the payload and/or armature surrounds the coils. In either type of system, when the electrical coils are energized, magnetic fields are generated along the length of the coilgun. In multi-coil coilguns, sequentially switching the electrical coils produces a wave of magnetic energy that travels along the length of the coilgun. Some coilguns push the launch package down the length with a magnetic field behind the package, while others both push and pull the launch package (referred to as push-pull) by selectively energizing coils on opposite ends of the launch package.
Both railguns and coilguns include an armature in the launch package. The armature is the portion of the launch package upon which electromagnetic forces act. In various systems, the armature is a separate item coupled to or integrated within a payload, is the payload itself, and/or is a sabot coupled to a payload. The design and operation of the armature for a railgun and a coilgun differs. However, in both types of electromagnetic launching system, the system acts on the armature to propel the launch package. The armatures are typically made from an electrically conductive material, such as iron, steel, copper, aluminum, etc. In some types of coilgun systems, the armature is generally a non-ferromagnetic material, such as copper or aluminum.